Oral pharmaceutical formulations comprising mesalazine are known, which are either tablets or granulate. The granulate may be packed in sachets. For the purposes of the present invention a “sachet” will refer to an envelope or bag for a granulate, while “granulate” refers to particles, granulate or spheronised particles.
Presently, tablets containing 250 or 500 mg mesalazine are known. Tablets of 250 mg typically weigh about 540 mg, i.e. they have a drug load of (250/540)% by weight=46% by weight. Tablets containing up to 84% by weight mesalazine have been described in the patent application WO 00/44353 with the title “Pharmazeutische Zusammensetzungen”.
For sachets, Dr. Falk Pharma has launched a product which claims to contain 500 mg mesalazine in a 930 mg sachet, corresponding to a drug load of 54% by weight.
Presently up to 4 g of mesalazine are often prescribed for the daily treatment of intestinal bowel diseases, such as Crohn's disease and Ulcerative Colitis.
If 4 g of mesalazine is administered in 250 mg tablets, the patient needs to swallow 16 tablets a day. Alternatively, 500 mg tablets may be administered, but with a drug load in the 50% range, the tablets will weigh about 1 g each, which many patients find rather large to swallow.
There exists a need to provide a product which allows administering large daily doses of drug without adversely affecting patient compliance.
Methods for manufacturing oral pharmaceutical formulations comprising mesalazine on an industrial scale are known. However, known methods of manufacture necessitate a high number of production steps to achieve a product having desirable release characteristics. This leads to cumbersome and expensive manufacture.